Inorganic direct methanol fuel cell

Significant commercial advances of direct methanol fuel cells (DMFC) continue to be hampered by several issues involving the use of proton exchange membranes (PEM). Reduced methanol efficiencies and catalyst poisoning occur as a result of the high methanol permeability of commercially available Nafion, a perfluorosulfonate polymer and the current mark for PEM performance in DMFC applications. The composite approach has recently been used to obtain reduced methanol permeability of the Nafion membrane while maintaining high power density. The objective of this research is to develop an inorganic, zirconium phosphate based proton conducting membrane/methanol fuel cell prototype suitable for full-scale application, which performance characteristics exceed those of polymer electrolyte membrane fuel cells. In parallel, the most important drawbacks of the currently developed commercial fuel cells, which are the high cost of investment and difficulties with water management, will be overcome. For application in a fuel cell, new fully inorganic membranes were developed including elastic inorganic matrix, impregnated with zirconium phosphate, antimonic acid, polytungsten acid, cesium salts. Their proton conductivity and temperature stability is sufficient for fuel cell applications. The method for crack-free membrane production was developed in such a way to allow upscale of the membrane area. For laboratory application, the membrane area was limited to 100 cm', IR, XRD, DSC, TGA, SEM and BET were used to characterise materials. Ionic conductivity was obtained by impedance spectroscopy. It was found that the surface area of the newly developed high conductive membrane is increased by two orders. Higher surface area explains higher proton conductivity, because zirconium phosphate is surface conductor.